Optical sensor device with reduced thickness and method for forming the same

Abstract

An optical sensor device and a method for forming the same are provided, including forming a curable transparent material on a substrate, wherein the substrate has a plurality of optical sensor units therein; providing a transparent template, which has a plurality of concaves; imprinting the curable transparent material with the transparent template to form a plurality of convexes corresponding to the plurality of concaves; and curing the curable transparent material to form a transparent layer having a micro-lens array. The step of curing the curable transparent material includes adhering the transparent template to the curable transparent material to act as a cover plate for the optical sensor device.

What is claimed is: 
     
       1. An optical sensor device, comprising:
 a substrate having a plurality of optical sensor units therein; 
 a first light collimating structure on the substrate, comprising: 
 a first transparent layer having a plurality of micro-lenses arranged in an array; and 
 a plurality of first light-shielding layers on the first transparent layer between the plurality of micro-lenses, wherein the plurality of first light-shielding layers does not cover the plurality of micro-lenses in a direction along a top surface of the substrate, and wherein the plurality of micro-lenses are convex portions of the first transparent layer without an interface between the plurality of micro-lenses and the first transparent layer; and 
 a transparent cover plate disposed on the first light collimating structure, wherein the transparent cover plate is formed of a single transparent material, and is in direct contact with the plurality of micro-lenses, wherein the first light collimating structure further comprises a plurality of second light-shielding layers on the substrate between the plurality of optical sensor units, and the plurality of first light-shielding layers correspond to the plurality of second light-shielding layers, respectively, and at least partially overlaps on a vertical projection direction. 
 
     
     
       2. The optical sensor device of  claim 1 , wherein the substrate further comprises a plurality of metal layers between the plurality of optical sensor units, and the plurality of metal layers correspond to the plurality of first light-shielding layers, respectively, and at least partially overlaps on a vertical projection direction. 
     
     
       3. The optical sensor device of  claim 1 , wherein a material of the first transparent layer is a curable transparent material. 
     
     
       4. The optical sensor device of  claim 1 , wherein materials of the first transparent layer and the transparent cover plate are different. 
     
     
       5. The optical sensor device of  claim 1 , wherein a refractivity of the first transparent layer is larger than a refractivity of the transparent cover plate. 
     
     
       6. The optical sensor device of  claim 1 , wherein the first light collimating structure further comprises a dam located on opposing sides of the first transparent layer. 
     
     
       7. The optical sensor device of  claim 1 , further comprises a second light collimating structure on the substrate. 
     
     
       8. The optical sensor device of  claim 7 , wherein the second light collimating structure comprises:
 a second transparent layer on the substrate; and 
 a plurality of third light-shielding layers on the second transparent layer and corresponding to the plurality of first light-shielding layers. 
 
     
     
       9. The optical sensor device of  claim 7 , wherein the second light collimating structure comprises:
 a plurality of transparent pillars on the plurality of optical sensor units within the substrate; and 
 a plurality of fourth light-shielding layers surrounding the plurality of transparent pillars. 
 
     
     
       10. The optical sensor device of  claim 1 , wherein the substrate further comprises a protective layer on the plurality of optical sensor units. 
     
     
       11. The optical sensor device of  claim 1 , wherein a thickness of the transparent cover plate occupies 20% to 40% of a thickness of the optical sensor device. 
     
     
       12. A method of forming an optical sensor device as claimed in  claim 1 , comprising:
 forming a curable transparent material on a substrate, wherein the substrate has a plurality of optical sensor units therein; 
 providing a transparent template, wherein the transparent template has a plurality of concaves; 
 imprinting the curable transparent material with the transparent template to form a plurality of convexes corresponding to the plurality of concaves; and 
 curing the curable transparent material to form a transparent layer having an array of micro-lenses, wherein the curing of the curable transparent material comprises adhering the transparent template to the curable transparent material to act as a cover plate for the optical sensor device. 
 
     
     
       13. The method of  claim 12 , wherein the providing of the transparent template comprises:
 providing a transparent material; and 
 patterning the transparent material to form the transparent template having the plurality of concaves. 
 
     
     
       14. The method of  claim 13 , wherein the patterning of the transparent material comprises imprinting the transparent material using another template. 
     
     
       15. The method of  claim 13 , wherein the patterning of the transparent material comprises performing a lithography process and an etching process on the transparent material. 
     
     
       16. The method of  claim 15 , wherein the lithography process comprises using a gray-scale mask. 
     
     
       17. The method of  claim 12 , further comprising forming a plurality of first light-shielding layers on the transparent template between the plurality of concaves before the imprinting of the curable transparent material with the transparent template. 
     
     
       18. The method of  claim 12 , further comprises forming a plurality of second light-shielding layers on the substrate between the plurality of optical sensor units before the forming of the curable transparent material on the substrate. 
     
     
       19. The method of  claim 12 , wherein the substrate further comprises a plurality of metal layers between the plurality of optical sensor units. 
     
     
       20. The method of  claim 12 , further comprises forming a dam on opposing sides of the substrate before the forming of the curable transparent material on the substrate. 
     
     
       21. The method of  claim 12 , further comprising forming a second light collimating structure on the substrate before the forming of the curable transparent material on the substrate.